Vibrator for rapping patterns in molding



0. S. HAMMOND.

VIBRATOR FOR RAPPING PATTERNS IN MOLDING.

APPLICATION FILED DEC-2, 1920.

PatentedSept. 12, 1922.

INVENTEIEL.

Patented Sept. 12, 1922.

UNITED STATES OLIVER S. HAMMOND, OF GUELPH, ONTARIO, CANADA.

VIBRATOR FOR RAPPING PATTERNS IN MOLDING.

Application filed December 2, 1920. Serial No. 427,810.

T all whom it may concern.

Be it known that I, OLIVER S. HAMMOND, of the city of Guelph, county of Wellington, Province of Ontario, Canada, have invented certain new and useful Improvements in Vibrators for Rapping Patterns in Molding, of which the following is aspecification.

This invention relates to devices for jarring or rapping patterns to loosen them in the sand and thus facilitate their withdrawal without breaking down the mould, and my object is to devise a construction which will be compact, which will be efficient in operation, and which may be constructed at reasonable cost.

I attain my objects by means of the constructions hereinafter described and illustrated in the accompanying drawings in which Fig. l is a longitudinal section of my improved vibrator; and m Fig. 2 a cross section on the jogged line a e in Fig. 1.

In the drawings like numerals of reference indicate corresponding parts in the different figures.

1 is the body of the casing of the vibrator and 2 the end caps screwed thereon. Between each end cap and the body of the ca ing is placed a hardened steel disk 3 against which the vibrator plunger 4; may strike. This plunger is provided with annular grooves 5 from which lead passageways 6 leading respectively to opposite ends of the plunger. 7 is the air inlet formed in the easing from which lead in opposite directions the inlet ports 9 communicating with annular grooves 10 formed in the inner face of the casing. Annular grooves 11 are also formed in the casing from each of which lead two exhaust ports 12, the outer parts of which are directed longitudinally of the casing so that the exhaust occurs in a direction away from the pattern to which the vibrator is attached so as to prevent the possibility of sand being blown on to the mold which is being made, which would cause bad castings.

The right hand steel disk 3 is provided vith a stud 13 which serves to position a coil spring 14, which is partly received in a recess in the adjacent end of the plunger 4:.

The mode of operation of the device will be apparent from an examination of the drawings. In the position shown in Fig.

1, .air is entering the various ports and passages to exert its pressure against the left hand end of the plunger to force it to the other end, and exhaust has taken place through the right hand exhaust ports. When the plunger reaches the other end of the casing, the air passes through the various passages and ports to operate against the right hand. end of the plunger to throw it back towards the left, the exhaust then taking place through the left hand exhaust ports. The spring 14 tends to return the plunger to the initial position and prevents any possibility of the plunger sticking on dead centre.

Outside the arrangement of the exhaust passages already referred to, the important feature of my invention is the use of the inlet and exhaust grooves in the casing of the device. This allows air pressure to pass all round the piston and reduces friction by giving the piston practically a floating fit in the casing. Further, any sand or other particles going into the intake will be received in these grooves and will not interfere with the working of the vibrator.

From the above description, it will be seen that I have devised a construction which will satisfactorily attain the objects of my invention as set forth in the preamble of this specification.

What I claim as-my invention is In a vibrator, the combination of a body having an air inlet and a pair of outlets formed in its sides; a plunger adapted to reciprocate in said body, the body having a pair of annular channels formed in its inner surface at each side of the centre of its length, one channel at each end being in communication at all times with the air inlet,

and the other channel. at each end being at all times in communication with an air outlet, and the plunger having an annular channel formed at each side of its centre, the channel at one side of the centre of the plunger being adapted to communicate with the inlet channel at the same side of the centre of the body while the other channel in the plunger is in communication with an outlet channel at the other side of the centre ber, 1920.

OLIVER S. HAMMOND. 

